net: usb: lan78xx: Connect PHY before registering MAC

[ Upstream commit 38b4fe320119859c11b1dc06f6b4987a16344fa1 ]

As soon as the netdev is registers, the kernel can start using the
interface. If the driver connects the MAC to the PHY after the netdev
is registered, there is a race condition where the interface can be
opened without having the PHY connected.

Change the order to close this race condition.

Fixes: 92571a1a ("lan78xx: Connect phy early")
Reported-by: NDaniel Wagner <dwagner@suse.de>
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Tested-by: NDaniel Wagner <dwagner@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/usb/lan78xx.c

@@ -3799,10 +3799,14 @@ static int lan78xx_probe(struct usb_interface *intf,
 	/* driver requires remote-wakeup capability during autosuspend. */
 	intf->needs_remote_wakeup = 1;
 
+	ret = lan78xx_phy_init(dev);
+	if (ret < 0)
+		goto out4;
+
 	ret = register_netdev(netdev);
 	if (ret != 0) {
 		netif_err(dev, probe, netdev, "couldn't register the device\n");
-		goto out4;
+		goto out5;
 	}
 
 	usb_set_intfdata(intf, dev);
@@ -3815,14 +3819,10 @@ static int lan78xx_probe(struct usb_interface *intf,
 	pm_runtime_set_autosuspend_delay(&udev->dev,
 					 DEFAULT_AUTOSUSPEND_DELAY);
 
-	ret = lan78xx_phy_init(dev);
-	if (ret < 0)
-		goto out5;
-
 	return 0;
 
 out5:
-	unregister_netdev(netdev);
+	phy_disconnect(netdev->phydev);
 out4:
 	usb_free_urb(dev->urb_intr);
 out3: